Summary of Evidence Base for Guiding Principles and Recommendations

Health Canada carried out its first Evidence Review Cycle for Dietary Guidance between 2013 and 2015, which is referred to as the ‘2015 Evidence Review’. This review looked at evidence from 2006 to 2015. Data gathering methods and findings are presented in detail elsewhere.[1]

Results of the Assessment of the Use of Eating Well with Canada’s Food Guide. This included results of the 2012 Canadian Community Health Survey Rapid Response module, which collected responses from 9700 Canadians on their awareness and use of the Food Guide.

Building on the 2015 Evidence Review, Health Canada continues to monitor the most recent evidence on food and health. Scientific reports that included extensive systematic reviews of the literature on food related topics were considered. High-quality, peer reviewed systematic reviews were also included. Strict inclusion criteria for selecting reports were set. For example, reports had to be published by a leading scientific organization or governmental agency and had to provide the grading of evidence. Exclusion criteria were also defined. For example, industry commissioned reports were excluded.

Evidence supporting Guiding Principle 1:

Dietary patterns

Association
between increased intakes according to the Dietary Approaches to Stop
Hypertension (DASH) pattern and decreased blood pressure or LDL cholesterol [2]

Association
between increased intakes according to Mediterranean-style, Portfolio or DASH
patterns and decreased LDL cholesterol or cardiovascular disease risk [3]

Saturated fatty acid replacement

Processed
meat

Association
between increased intakes of processed meat (meats processed by smoking, curing
or salting, or addition of chemical preservatives) and increased risk of
colorectal cancer [15]

Evidence
supporting Guiding Principle 3

Health
Canada recognizes that knowledge and skills are needed to apply Guiding
Principles 1 and 2 and subsequently improve diet quality and health outcomes.
The evidence for Guiding principle 3 is primarily drawn from Health Canada’s
analysis of the evidence and describes the Canadian context and the settings in
which skills can be learned at any stage of life.[16]

Home
food preparation and health

The research on the relationship between
home food preparation and health is limited; however, available evidence
suggests that home food preparation may be associated with diets that are
consistent with healthy eating recommendations.[17]

Canadian context

There has been a shift from cooking fromscratch towards use
of pre-prepared, packaged and convenience foods, which require fewer or
different skills.[18]

Canadian
households have significantly increased the proportion of the food budget that
is spent on ready-to-eat or ready-to-heat convenience foods.[19]

On average, Canadian households spend about 30 percent of
their food budget on meals and snacks purchased from restaurants, cafeterias,
vending machines and other ‘away from home’ sources.[20] Meals
eaten away from home can increase the amount of calories, sodium, sugars and
saturated fat in the diet.[21]

[2] American College of Cardiology/American Heart Association 2013: Guideline on lifestyle management to reduce cardiovascular risk: a report of the ACC/AHA task force on practice guidelines; Dietary Guidelines Advisory Committee 2015: Scientific report of the DGAC: Advisory report to the Secretary of Health and Human Services and the Secretary of Agriculture.

[3] American College of Cardiology/American Heart Association 2013: Guideline on lifestyle management to reduce cardiovascular risk: a report of the ACC/AHA task force on practice guidelines; Canadian Cardiovascular Society 2016: Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in the Adult.

[5] Health Canada 2015: Summary of Assessment of a Health Claim about Vegetables and Fruit and Heart Disease.

[6] Canadian Cardiovascular Society 2016: Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in the Adult.

[7] Health Canada 2015: Summary of Assessment of a Health Claim about Soy Protein and Cholesterol Lowering; Canadian Cardiovascular Society 2016: Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in the Adult.

[9] Health Canada 2012: Summary of Assessment of a Health Claim about the Replacement of Saturated Fat with Mono- and Polyunsaturated Fat and Blood Cholesterol; Dietary Guidelines Advisory Committee 2015: Scientific report of the DGAC: Advisory report to the Secretary of Health and Human Services and the Secretary of Agriculture; Dietary Guidelines Advisory Committee 2010: Report of the DGAC on the Dietary Guidelines for Americans; World Health Organization. 2016: Effect of trans-fatty acid intake on blood lipids and lipoproteins: a systematic review and meta-regression analysis; World Health Organization 2016: Effects of saturated fatty acids on serum lipids and lipoproteins: a systematic review and regression analysis.

[10] World Health Organization 2012: Guideline: sodium intake for adults and children; American College of Cardiology/American Heart Association 2013: Guideline on lifestyle management to reduce cardiovascular risk: a report of the ACC/AHA task force on practice guidelines; Dietary Guidelines Advisory Committee 2010: Report of the DGAC on the Dietary Guidelines for Americans; National Health and Medical Research Council 2011: A review of the evidence to address targeted questions to inform the revisions of the Australian Dietary Guidelines.

[11] Dietary Guidelines Advisory Committee 2015: Scientific report of the DGAC: Advisory report to the Secretary of Health and Human Services and the Secretary of Agriculture.

[12] Dietary Guidelines Advisory Committee 2010: Report of the DGAC on the Dietary Guidelines for Americans.

[14] Health Canada 2012: Summary of Assessment of a Health Claim about the Replacement of Saturated Fat with Mono- and Polyunsaturated Fat and Blood Cholesterol; Dietary Guidelines Advisory Committee 2015: Scientific report of the DGAC: Advisory report to the Secretary of Health and Human Services and the Secretary of Agriculture; Dietary Guidelines Advisory Committee 2010: Report of the DGAC on the Dietary Guidelines for Americans; World Health Organization. 2016: Effect of trans-fatty acid intake on blood lipids and lipoproteins: a systematic review and meta-regression analysis; World Health Organization 2016: Effects of saturated fatty acids on serum lipids and lipoproteins: a systematic review and regression analysis.

[16] Government of Canada. A
Look at Food Skills in Canada. Ottawa, 2015; Government of Canada. Improving
Cooking and Food Preparation Skills: A Profile of Promising Practices in Canada
and Abroad. Ottawa, 2010.